Realization of Intelligent Network in the next generation network
Http://www.chinatelecom.com.cn May 27, 2003 Zhang Xueli
In the next generation network, the smart network is located in the business plane and provides users with a variety of intelligent services. From the current technology development and business maturity, in the next generation network, the smart network has three different implementations: soft exchange access to the traditional smart network SCP; traditional intelligent network SSP access application server; use third parties for IAD Users, SIP users, H.323 users, PSTN, etc. provide a variety of intelligent network services. In the next generation network, the smart network still requires the business exchange function (SSF), the service control function (SCF), the service data function (SDF), the dedicated resource function (SRF), etc., to complete business trigger, business control, dedicated The provision of resources and the bill of intelligence calls. In different implementations, these functional entities and physical devices will have different mapping relationships, and the interaction between entities, the users and billing methods of the smart network are also different. I. Softswitch Access the SCP of the traditional smart network In this manner, the intelligent business is still provided by the SCP of the traditional smart network. Softswate implements the SSF function, responsible for the trigger of intelligent services, then pass the signaling gateway and the traditional intelligent network SCP intercom, accepts SCP control, complete call continues, and interaction with users, providing smart network services for IAD users, SIP users, H.323 users, PSTN, and other users. The current soft switching device supports the INAP protocol of the smart network. Therefore, soft exchange can be interacted with the traditional fixed intelligent network of SCP, obtain the billing card provided by the original fixed intelligent network, called centralized payment, virtual private network and other intelligence Internet business. In the future, if the soft exchange supports the CAMEL system's CAP protocol, the WIN system's WIN MAP protocol, then soft exchange can also be used as SSF in GSM and CDMA networks, access SCP in GSM and CDMA networks, providing a variety of intelligent services for mobile users. With softswitch access fixed smart network SCP to provide services to the IAD user using the H.248 protocol, the specific implementation process is: the soft switching device provides an SSF function, and after receiving a call from the IAD user, according to the number dial dial Trigger the intelligent service; use the INAP protocol to access the traffic control point (SCP), SCPs in the fixed smart network, SCP, SCF functions of service data; for SRF functions, depending on the location of the private resource Unlike the device functionality, three different implementations are provided by independent IP, secondary relay and soft exchange for SRF. When providing SRF functions from independent IP, the recording notification required by the smart network business is provided by the intelligent peripheral (IP) in the traditional smart network, soft exchange triggers intelligent service, soft exchange through signaling gateway (SG) and SCP interaction INAP When the SCP indicates that the softswitch establishes a temporary connection to the IP, the soft exchange uses the ISUP / TUP to use the IP / TUP through SG. When providing SRF functions by the auxiliary relay, the recording notification required by the smart network business is provided by the SSP in the traditional smart network, and the softswitch triggered the intelligent service. Use INAP to interact with SCP through signaling gateway (SG), when SCP indicates soft When switching to the provisional connection to SSP, the soft exchange uses the ISUP / TUP to establish a connection to the auxiliary SSP via SG, providing dedicated resource functions by the auxiliary SSP. When the SRF function is provided by softswitch, the recording notification required by the smart network business is provided by soft exchange. Softswitch triggers intelligent services. Use INAP to interact with SCP, when playback notification, by SCP Indicates softswitch to provide dedicated resource functions. Prerequisite to use this method is soft exchange to provide SRF resources.
For these three different implementations, the signaling between SCP and soft exchange between SRF functions is required to interact with the user; signaling for call monitoring, control, and continuous process, soft exchange and SCP interaction It is consistent. In the next generation network, the intelligent network is implemented, in addition to completing normal business control and call continues, billing is also a very important issue. In the way in softswitch access to the traditional intelligent network SCP, the billing of the smart network service is completed by the SCP control soft switching device of the traditional smart network, and the ACR returned by the softswitch is accumulated or deducted. Second, the traditional intelligent network SSP Access Application Server This mode is provided by the application server, and the SSP of the traditional intelligent network accesses the application server through the signaling gateway, and the application server is connected to the corresponding protocol stack according to different network calls. And determine the business logic you need to call, provide intelligent services for PSTN, GSM, and CDMA users. When the SSP of the traditional intelligent network accesses the application server, the application server and the traditional interactive network of SSP / IP / HLR, complete the logical control, call continuation, and private resources provided by the traditional smart network according to the needs of business logic. If the service needs, the application server can also communicate with the service control point (SCP), complete access to business data or user data. When the original PSTN user, GSM user or CDMA user uses smart network traffic, the SSP of the original network will trigger the corresponding intelligent service according to the number or signing information dial, and then send a business request to the application server through the signaling network. , Execution of the application server control service, the signaling gateway completes the conversion between the seven signaling and the IP protocol to carry the upper layer of intelligent network protocol (the INAP protocol of the PSTN, the CAP protocol of the GSM network, Win Map of the CDMA network protocol). The traditional intelligent network SSP accesses the application server, in addition to the required signaling gateway to complete the signaling conversion, the traditional smart network SSP accesses the SCP to implement the smart network, in which case the application server is consistent with SCP, ie Complete Business Control Function (SCF) and Business Data Functions (SDF). In this way, the accounting mode of the intelligent business is different depending on the network of services. For the call of the PSTN smart network, the application server notifies the specific billing category, the billing discount, etc., the billing SSP is notified, and then bill the call according to the billing result returned by the SSP; for the Call for GSM intelligent network Calculate call costs by the application server according to the call time returned by GSM SSP; for the CDMA smart network, the application server calculates the specific call duration and call fees based on the response and disassembly information reported by the CDMA SSP. Third, the other feature of using third parties to achieve the next generation of intelligent services is to have open interfaces, providing various open APIs, such as the Parlay API provides a creation platform for the development of third-party business. In the next-generation network based on softswitch, you can also provide smart network services through a variety of users of IAD users, SIP users, H.323 users, PSTN, and intelligent services are provided by third-party applications. After the softswitch receives the user's call, send a SIP message to the application server according to the call information, the application server calls the third party by the API interface according to the received call information, and controls the implementation of the intelligent service. The following is based on the billing card service (300 business) call setup process as an example. In the next generation network, the third-party application, application server, soft exchange, and media server interface relationships are used in the next generation of applications to implement intelligent services. . Among them, the third-party application and application server is the PARLAY API protocol, and the application server and soft exchange are the SIP protocol, and the media server is an MGCP protocol.
(1) For 300 business, third-party application calls Enable call notification, request application server to monitor network information; (2) User A Dial 300 Business Access Code, soft exchange sends an Invite message to the application server; (3) Application Server to soft Exchange return 100 response; (4) Application server calls the Event Notify API, apply user a dial information to third-party applications; (5) Apply call CREATE UI Call, require application server to establish a connection to the media server; (6) Application Server Send CRCX to the media server, establish a connection; (7) The media server retires the RES response to the application server; (8) The application server returns a 200ok response to the soft exchange, indicating that the INVITE of the soft exchange is successful; (9) Softswitch Route Res response to the application server; (10) Application call send INFO AND COLLECT REQ, the player Please select the type of the voice of the voice; (11) Application Server Sends the RQNT to the media server, requires the media server to play and collect user input information; (12) Media server returns the res; (13) The Media Server sends NTFY to the application server, notifies the playback completion, and notifies the application server to the application server; (14) Application Server returns the RES response to the media server; 15) Application Server callback sending Send Info and Collect RES, sending the user's language to third-party applications; (16) Third-party application call send info and collect req, show the user to enter the card number; (17) Application Server Send RQNT to The media server requires the media server to play and collect user input information; (18) Media server returns RES; (19) Media server sends NTFY to the application server, notify the play-up completion, and notify the application server (20) Application Server returns the RES response to the media server; (21) Application Server callback Send Info and Collect RES, give the user input card number to third-party applications; (22) Third-party application call send info and collect req, put Tonic user input password; (23) Application Server Sends RQNT to Media Server, requires media server to play and collect user input information; (24) Media server returns the res; (25) Media Server Send NTFY to the application server, notify the play Completed, and notify the application server to the application server; (26) Application Server returns the RES response to the media server; (27) Application Server Tune Send Info and Collect RES,
